1. Field of the Invention
This invention relates to an oil dispersant formulation and a process for dispersing spilled oil on water. More particularly, a formulation of chemical surfactants and solvent results in a low toxicity dispersant which is effective at dispersing oil at low concentrations under a wide range of weather conditions.
2. Description of the Related Art
One of the technologies used for oil spill response involves the use of chemical dispersants. The application of chemical dispersants is dependent on several factors: (1) weather conditions, (2) nature of the oil spilled, (3) area to be covered and (4) adequacy of equipment and supplies. Although it is highly desirable, it has not been possible to provide a single chemical dispersant formulation which will treat all oils under all conditions. For example, it is much more difficult to disperse a high-boiling viscous oil such as bunker oil as compared to a light crude oil. Furthermore crude oils and oil products vary widely in their properties including ability to be dispersed.
A desirable property for chemical dispersants used to treat oil spills is that the surfactant formulation of the dispersant results in very low oil-water interfacial tension such that the oil is effectively dispersed as fine oil droplets in water without coalescing even at low dispersant to oil ratios. Also, the dispersant formulation should be of minimal toxicity so that it does not add to the environmental damage caused by the oil spill.
Various dispersant formulations have been advanced for treating oil spills. U.S. Pat. No. 3,793,218 discloses a dispersant formulation for dispersing oil slicks. U.S. Pat. No. 4,560,482 relates to a dispersant composition for treating oils having viscosities of from 1000 to 10,000 cp in water.